Method and device for treatment of the spine

ABSTRACT

A device and method of positioning materials in a spine using an arcuate tool and introducer. Materials may be positioned as desired, such as against an inner annular wall of an intervertebral disc or vertebral body. The arcuate tool retains its predetermined arcuate shape when no pressure or force is applied to the tool, and is positioned by manipulating the tool relative to an introducer and the spine, with the introducer manipulated relative to the spine.

Applicant claims the benefit of U.S. application Ser. No. 11/972,815filed Jan. 11, 2008.

Applicant claims the benefit of U.S. application Ser. No. 11/112,475filed Apr. 23, 2005, now Issued U.S. Pat. No. 7,322,962 issued Jan. 29,2008, which claimed the benefit of U.S. Provisional Application Ser. No.60/564,838 filed Apr. 23, 2004, and which claimed the benefit of U.S.Provisional Application Ser. No. 60/572,930 filed May 20, 2004, andwhich claimed the benefit of U.S. Provisional Application Ser. No.60/586,627 filed Jul. 9, 2004 and which claimed he benefit of U.S.Provisional Application Ser. No. 60/588,582 filed Jul. 16, 2004, andwhich claimed the benefit of U.S. Provisional Application Ser. No.60/588,587 filed Jul. 16, 2004.

FIELD OF INVENTION

This invention and method relate to the treatment of spine or evacuationof components of the spine.

BACKGROUND OF THE INVENTION

The intervertebral disc is comprised of an outer annulus fibrosis and aninternal nucleus pulposus. The healthy annulus is comprised of 10-20lamellae forming a concentric ring of collagen and elastic fibers aroundthe nucleus while the healthy nucleus pulposus is ovoid and composed ofa gelatinous mucoprotein within the confines of the annulus fibrosis.

In the healthy normal disc, the annulus is thick and the internal wallis strong and without significant defects. Aging and trauma causemultiple and varied defects of the annulus as well as changes in thenucleus. These defects are a source of pain for many individuals. It iswidely accepted that the defects which actually do cause pain are eitherposterior or postero-lateral. By far, it is most common that symptomaticdefects are posterior and/or unilateral postero-lateral. Symptomaticdefects which are posterior and bilateral postero-lateral certainly doexist but are definitely less common. On the other hand, degenerativechanges with defects along the inner annular wall can be found commonlyin various other segments of the inner annular wall (anteriorally,antero-laterally on either or both sides, and laterally on either orboth sides. These defects are understood to be asymptomatic, butnevertheless are common.

Radiofrequency is used to treat internal intervertebral disc disruption.Forward pressure is applied to circumvent the nucleus adjacent to theinner annular wall, leverage with the forward pressure against theannular wall opposite to the portion attempting to be treated, or drivethrough the annular tissue which is intended to be treated.

The catheter is advanced around the inside of the nucleus pulposusadjacent to the inner annular wall. However, in the spectrum of discsrequiring treatment, ideal discs are infrequently encountered. Theresult is that the tip of the catheter, even with a bent and/or cappedtip gets caught in defects in the wall, making the advancement difficultor impossible. This frequently results in kinking of the catheter (whichthen typically must be removed), lodging into the defect (presumablyworsening the defect), going through the annular wall (obviouslycreating a through and through defect in the annular wall and evenpotentially puncturing or damaging nerve or vascular structures), andultimately making the intended treatment sub-optimal or even impossible.Additionally, in such situations there has been further damage caused tothe disc by the catheter. The defects into which the catheter caninadvertently probe can be the defect, or defects, intended to betreated. Alternately, a defect in the anterior, antero-lateral, orlateral wall can equally be entered inadvertently and cause a disruptionof the procedure. Degenerative disc walls commonly contain multiple suchdefects, as well as thinning of the wall, which are all too frequentlypenetrated.

The insertion of material into the disc or vertebral body can strengthena diseased or damaged disc or vertebral body. Such materials may beman-made, or the materials may be biological materials. Regenerativematerials show great promise in regenerating damaged and diseasedtissue. Proper positioning of these materials within a disc or avertebral body may be important in achieving desired results.

SUMMARY OF THE INVENTION

The invention is device and method for positioning materials within anintervertebral disc or vertebral body. The device and method allowpositioning of the material at substantially all points of the disc andvertebral body, and particularly on the posterior and postero-lateralportions of the inner annulus of the disc. An introducer facilitatesinsertion of the elongated placement tool. The arcuate, and preferablyS-shaped, elongated placement tool is formed within a guide or lumen ofthe introducer, and the elongated placement tool assumes itspredetermined arcuate shape when no pressure or force is applied to thetool by the introducer.

In another embodiment, an elongated tool is used to progressively removematerial from the interior of the mammalian intervertebral disc orvertebral body.

DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a partial lateral view of a portion of a human spine.

FIG. 2 is a sectioned view taken essentially along line 2-2 of FIG. 1

FIG. 3 demonstrates a device for placing material or objects andremoving material or objects and positioned within an intervertebraldisc or vertebral body.

FIG. 4 is an exploded view showing the introducer, non-conductivesheath, stylet and catheter.

FIG. 5 shows the introducer with stylet in place and having penetratedthe annular wall of the disc.

FIG. 6 shows the introducer with the stylet removed.

FIG. 7 shows the non-conductive sheath inserted into and through theintroducer, with the S-shaped catheter advanced through the sheath.

FIG. 8 shows the S-shaped catheter extended as required through thesheath.

FIG. 9 demonstrates the introducer and sheath being retracted toposition the catheter.

FIG. 10 shows the introducer and sheath retracted, and the catheterpositioned against the inner annular wall defect.

FIG. 11 demonstrates the device being withdrawn from the disc and theiatrogenecally created defect being sealed.

FIG. 12 demonstrates a range of permissive angles of insertion of theintroducer relative to the disc.

FIG. 13 demonstrates the introducer penetrating the annular wall at adifferent angle from that shown in FIGS. 5 through 11.

FIG. 14 demonstrates another angle of entry of the introducer into thedisc.

FIG. 15 demonstrates a catheter having multiple orifices therein throughwhich materials may be dispensed.

FIG. 16 is a sectioned view of an introducer inserted into a sheathhaving ports therein.

FIG. 17 is a sectioned view of an introducer having ports through whichmaterials may be inserted into the disc, or from which materials may beremoved, such as by vacuuming, and also showing a cutter therein.

FIG. 18 demonstrates an introducer and stylet penetrating a disc.

FIG. 19 demonstrates the flexible tip bending on contact with the innerannular wall.

FIG. 20 demonstrates a cutter which may be used to remove material fromthe disc.

FIG. 21 demonstrates removal of a path of disc material using a cutterand a lavage/suction.

FIG. 22 demonstrates a progressive step in removing material from thedisc.

FIG. 23 demonstrates an additional progressive step in removing materialfrom the disc.

FIG. 24 demonstrates yet an additional step in removing material fromthe disc.

FIG. 25 is a sectioned view of an introducer with a trocar presenttherein.

FIG. 26 is a sectioned view of the introducer with a retractor therein.

FIG. 27 is an oblique partial view of a mammalian spine.

FIG. 28 is an oblique partial view of the mammalian spine with aretractor in position.

FIG. 29 is a sectioned view of a sheath.

[FIG. 30 is a sectioned view of a sheath and introducer with a cutter,fiber optic source and lavage and suction in place.

FIG. 31 is plan view of a mammalian intervertebral disc showing aportion of the disc evacuated according to the method of the invention.

FIG. 32 shows placement of a support member within the intervertebraldisc.

FIG. 33 shows a progressive step of the disc being evacuated accordingto the method of the invention.

FIG. 34 shows an additional support being positioned within the disc.

FIG. 35 shows an additional progressive step of the disc being evacuatedaccording to the method of the invention.

FIG. 36 shows an additional support being positioned within the disc.

FIG. 37 shows an additional progressive step of the disc being evacuatedaccording to the method of the invention.

FIG. 38 shows an additional progressive step of the disc being evacuatedaccording to the method of the invention.

FIG. 39 demonstrates a device for removing material or objects and froma vertebral body or intervertebral disc.

DESCRIPTION OF PREFERRED EMBODIMENTS

Turning now to the drawing figures, FIG. 1 shows a partial view of amammalian spine, and more particularly, a human spine 2. FIG. 2 is asectioned view taken essentially along line 2-2 of FIG. 1, and shows anannular wall of a disc 4 of a human spine. The inner annular wall isrough, or jagged, due to trauma, aging and/or disease. Treatment of theportion of the disc labeled 6 is indicated due to its condition.Advancement of a catheter into the disc, and around the wall of the discto the area to be treated is difficult, since the tip of the catheter islikely to engage the rough, jagged inner annular wall. The catheter ispreferred to be laid against the portion of the disc intended to betreated, minimizing the course of the catheter within the disc, yetassuring good contact of the catheter with the portion of the disc to betreated. The angle of entry into the disc should be maximized toaccommodate a spectrum of operative conditions and introducer/needleplacements. The portion of the disc requiring treatment as contemplatedin this embodiment is postero-lateral (one side or both), plus or minusa portion of the posterior wall. The route to the interior of the discmust be straight. For humans, the distance from the outer layer of skinto interior of the disc is approximately 12 to 30 centimeters, dependingupon the size of the individual upon which the process is performed.

FIG. 4 shows the primary elements of the apparatus of the presentinvention. A stylet 8 is inserted into an introducer 10. A lumen in theform of a sheath 12 is subsequently inserted into the introducer, and acatheter 14 having a preformed S shape is advanced through the sheath.The lumen acts as a guide through which the S-shaped tool such,catheter, is transported. The guide may take other forms that willassist transportation of the tool into the disc, such as a track or awire that the tool engages. In one embodiment, the guide is part of theintroducer, such as a lumen formed therein. The introducer is preferredto be straight for ease of placement and due to the distance from theskin to the interior of the disc. The introducer will generally have alength in excess of 10 centimeters.

The stylet and introducer, which may be needle like, form a passage intothe disc through the posterior wall of the disc on the side oppositethat requiring treatment. The stylet is intended to keep the tissue fromaccumulating within the advancing introducer.

The introducer is advanced under fluoroscopic guidance lateral to thesuperior articular process. The annulus is punctured and the introducermay be advanced initially approximately one-third to one-half of thedistance of the disc, as can be judged by operators skilled inperforming such procedures.

FIG. 5 shows the introducer with stylet in position. The sharp point ofthe stylet is driven through the wall of the disc, along with theintroducer. The stylet is then removed. FIG. 6.

After the stylet and introducer pierce the annular wall of the disc andaccess the interior of the disc, the stylet is removed and is replacedwith a lumen, which may be a sheath. A pre-formed, S-shaped catheter orother tool having memory retention properties is contained within thestraight sheath. The straight sheath is inserted through the introducerfor introduction into the disc. The catheter is straightened by thepressure from the walls of the sheath, but the catheter regains itsS-shape as it exits the sheath.

The sheath locks into place at the external end of the introducer. Whenlocked into place, the catheter sheath will protrude from the tip of theintroducer. The sheath remains well contained within the disc nucleusand not in the proximity of the opposing annular wall but may beadvanced or retracted as necessary for catheter positioning.

The sheath is preferred to be made of nonconductive material havingthermal insulative properties sufficient to avoid undesired heating oftissues and structures outside of the disc, even if the heating portionof the catheter comes into close proximity or even contact with thissheath. The sheath may be straight, or slightly curved, and capable ofadvancing through the introducer once the stylet is removed. It hassufficient rigidity to maintain a portion of the catheter in a straightposition while that portion of the catheter is in the sheath. The sheathis capable of externally locking at an upper portion into the introducerat the hub.

The non-conductive catheter sheath ensures that no inadvertent heatingof the introducer occurs. Heating may cause significant unwanted damageto skin, subcutaneous tissue, fat, muscle, and even nerve.

The sheath is inserted into the lumen of the introducer, while theintroducer remains in position within the disc as shown in FIG. 6. InFIG. 7, the catheter is advanced through the sheath. As the S-shapedcatheter exits the sheath within the interior of the disc, the catheter,due to memory retention properties, and with no pressure applied,assumes its S-shape, as shown in FIG. 7. In FIG. 8, the cathetercontinues to advance and contacts the lateral inner annular wall of theside on which the postero-lateral wall is to be treated. Catheteradvancement may be fluoroscopically monitored.

FIG. 9 demonstrates the introducer being retracted from the disc as thecatheter is advanced. This combination of movements causes the catheterto move toward the postero-lateral and posterior wall which is theintended side of treatment. As shown, the introducer and sheath areretracted until the catheter is in position against the site to betreated. Positioning of the sheath and the catheter may be monitoredfluoroscopically.

As shown in FIG. 10, the introducer is retracted until the catheterrests against the lateral posterior wall to be treated. The lateralposterior wall to be treated is opposite the side of the posterior wallthat the introducer has penetrated. Heat or radio frequency can beapplied to the disc wall by means of the catheter. Other therapeuticprocedures may be applied by use of an appropriate catheter. Thecatheter may then be retracted, and the introducer is retracted from thedisc as shown in FIG. 11. Either the tip of this catheter can bedifferentially heated to seal the entry defect, or the S shaped catheteris removed and replaced with a straight catheter with a heating elementat the tip. Heating of the tip as the introducer and elongated tool,such as the catheter, are withdrawn seals the entry defect. Alternately,a catheter with a portal at the tip to inject a sealant of this entrydefect may be used.

For positions between the extremes of acute and obtuse, the length ofsheath or elongated tool versus disbursed catheter will determine theposition at which the catheter tip will come into contact with theopposite lateral wall. Recognition of the goal of having the cathetercontact the mid portion of the lateral wall of the side to be treated,and monitoring progress under fluoroscopy will facilitate ideal catheterplacement.

In this embodiment, the portion of the elongated tool, such as acatheter, has an S shape when no material pressure or force is appliedto the catheter. The catheter may be formed of nitinol, which issufficiently flexible to be advanced through a straight lumen or sheath,but will regain the preformed arcuate or S-shape when present within theinterior of the disc. The catheter should also be sufficiently flexibleto conform to the shape of the disc wall, such as the posterior wall ofthe inner disc, when positioned against the wall. FIG. 10.

The S-shaped catheter allows the physician to treat the posterior wall,and particularly the lateral posterior wall, of a defective disc withoutthe necessity of first contacting the anterior wall with the catheter.The device and process prevent the end or tip of the catheter fromcatching or hanging against the rough interior annular wall, which mayhave many crevices that make it difficult to advance the catheter alongthe wall. The S-shaped catheter allows the catheter to be introducedinto the interior of the disc, and then positioned by manipulation ofthe introducer and catheter, without subjecting the catheter to beingsnagged by defects in the disc. The S shape facilitates good contact ofthe catheter with the postero-lateral segment of the disc even if theangle of the introducer entry is suboptimal. Additionally, the S shaperetards the catheter traversing through any large segment of theinterior of the disc which is typically filled with debris. Thisminimizes “shoveling” of the debris toward the segment of the innerannular wall to be treated.

Catheters may contain heating segments of various lengths. A finalheating element, which is contained in each of these types of catheters,may be present directly at the tip, and is used for the spot sealing onexit from the inner annular wall. An additional embodiment has astraight catheter with a heating element at the tip.

On withdrawal of the catheter, the end or tip of the catheterstraightens as it is exiting the annular wall. Spot heating at thisposition by tip 16 seals the defect that was created by the introducerand catheter.

FIG. 12 demonstrates an acceptable range of angles of introducerinsertion 18 when driving the introducer into the disc. The acceptablerange of angles is within about 70 degrees, but is not less than fortyfive degrees. Due to the S shaped configuration of the catheter, aprecise entry of the introducer is not required.

As shown in FIG. 13, acceptable results are achieved with the S-shapedcatheter used according to the novel method, even though the angle ofinsertion of the introducer varies from that shown in FIG. 10. Likewise,the angle of introducer insertion may be varied as shown in FIG. 14. Theintroducer may be withdrawn from the position shown in FIG. 14 to theinterior, posterior annular wall, and S-shaped catheter is capable ofbeing positioned against the lateral posterior wall of the disc by themethod stated above.

The catheter may provide heat or radio frequency for the purpose oftreatment of the disc. Other therapeutic applications may be used withthe device and method. Further, a catheter 20 may have multiple orificesfor the purpose of delivering materials such as adhesives, sealants orfillers into the disc. FIG. 15. A substance 22 may be injected throughthe catheter to the affected site to seal chemically, or otherwise, asopposed to thermally, defects including fissures and tears in theannular wall. Pressure manometery or fibro-optical viewing are alsopossible uses of this catheter system.

FIG. 16 shows a second embodiment of the device, wherein the sheath hasports 32, 34 formed therein. The stylet is shown in position in theintroducer of this embodiment. The stylet and introducer are used toaccess the interior annulus of the disc and shown in FIG. 18.

After entry into the disc, the stylet is withdrawn. The ports of thesheath may be used to insert materials into the disc, or removematerials from the disc. A vacuum may be applied to the ports for thepurpose of removal of material.

FIG. 19 shows a flexible deformable tip of the sheath. Deformation ofthe tip, which may be visualized fluoroscopically, defines hitting theinner annular wall. In one embodiment, 0.5 centimeters is sufficientprotrusion of the sheath, such that it can be observed to bend when itcontacts opposite inner annular wall. The bending of the tip of thesheath defines the limit of the inner annular wall immediately acrossfrom the entrance of the introducer complex into the disc. The limit ofthe inner annular wall opposite to the introducer insertion may bedefined when fluoroscopically viewed.

As shown in FIG. 17, a rotary cutter 36 is contained within the sheath.The rotary cutter is used to cut away material as the introducer iswithdrawn. FIG. 21. Alternately, another type of cutter may be used.

When the introducer, sheath and cutter complex are in the nucleus, thetip of the flexible sheath is advanced by external manipulation suchthat it protrudes from the introducer. The threaded probe protrudes fromthe sheath, such as by 2-3 mm. The rotating threaded probe is activatedto rotate within the inner annular wall. The initial “pass” of therotating threaded probe is accomplished by withdrawing theintroducer/sheath/probe linearly back to the position where theintroducer/sheath tip is at the level of the opening into the innerannular wall as previously defined. The complex is then advanced back toits position at the opposite inner annular wall as previously definedfluoroscopically. The sheath/probe is kept in its current position whilethe introducer is withdrawn a pre-defined distance, such as 5 mm in oneembodiment. The complex is again withdrawn with probe rotating. Anadditional amount of material is removed, similarly to mowing a lawn. Ifan additional amount of material is present between the first and secondprobe withdrawals, the amount of withdrawal can be modified to be lessthan, for example, 5 mm. In successive fashion, the complex is advanced,the introducer 40 withdrawn, the rotation of the treaded probe isstarted, the sheath/probe, and then the introducer segment, is withdrawnuntil the final sheath/probe withdrawal is accomplished with theintroducer tip at the level of the insertional inner annular wall. Sincethe sheath is S shaped, short lengths of sheath protruded from theintroducer will be arcuate. Incrementally longer segments of exposedsheath assume varying degrees of the S shape. This process verythoroughly evacuates the approximately half of the nucleus that isinitially addressed. At this point, the sheath/probe is withdrawn intothe introducer. The sheath/probe is rotated substantially 180 degreeswithin the introducer. The process is then repeated in the same fashionon the opposite half of the nucleus. Infusion of a substance, whichcould be normal saline, via a side portal 32 into the sheath,alternating with suction at portal 34, may be performed at intervals tofacilitate removal of the nuclear contents.

The sheath has a pre-formed S shape, and a memory for the S shape.Accordingly, as the rotary cutter is extended from the introducer, thesheath will continue to curve slightly, which allows material 42 whichis adjacent to the cut taken in FIG. 21 to be removed. FIG. 22. As therotary cutter cuts material away, lavage/suction are applied through theports 34 of the introducer. One port allows for infusion of a substance(which may be normal saline) into one port. The other port is forsuction or other form of removal of material including debris from thedisc. By increasing the length of the S-shaped sheath from theintroducer 40, additional passes each take material from the disc, asthe cutter is further extended from the sheath. FIG. 23 demonstrates thecutter after the cutter has made six passes, and is beginning a seventhpass. In each pass, the arcuate shape of the sheath as it is extendedwhich allows for progressively removing from the interior of the disc.Shorter segments of the sheath exposed from the introducer have anarcuate shape allowing for an infinite number of paths throughout thedisc enabling the removal of nuclear material if needed.

After the material is removed from one side of the disc, the cutter isretracted into the introducer. The cutter and/or the sheath are rotated180 degrees, so that the S shaped cutter is present on the opposite sideof the disc. The sheath containing the cutter is extended from theintroducer on each subsequent pass as needed, until material is removedas desired from the disc as shown in FIG. 24.

FIG. 25 shows a trocar 50 that is a present within an introducer 52. Thetrocar may be a relatively large stylet. FIG. 26 shows a retractor 54that is present within the introducer. The retractor manipulates thenerve root 56.

FIG. 27 shows a vertebra 58 of a mammalian spine, an additional vertebra60 of a mammalian spine, with an intervertebral disc 62 between thevertebrae. Also shown are a pedicle 64, a superior articular facet 68and an inferior articular facet 66. The nerve root 56 is shown astraversing the intervertebral disc. As shown, the position of the nerveroot interferes with access to the intervertebral disc. FIG. 27 is anoblique view demonstrating what is typically visualized flouriscopicallyfor intradiscal procedures, except for the nerve root, which does notvisualize under fluoroscopy, but whose position is known to anexperienced operator.

The trocar is used to pierce and penetrate skin and other tissue. Uponreaching the nerve root, the trocar is removed and the retractor isinserted. The retractor is used to lift the nerve root over theintroducer, so that the nerve root is out of the way, and does notinterfere with access to the intervertebral disc. FIG. 28.

Once the retractor has repositioned the nerve root over the introducer,the retractor may be removed from the introducer, and the trocarreinserted into the introducer. With the nerve root positioned over theintroducer, the nerve root will not be damaged as the trocar andintroducer are inserted into the intervertebral disc. The trocar piercesthe intervertebral disc for access to the disc with the introducer.

FIG. 29 demonstrates a cross section of a sheath 70 that is used toevacuate a defective disc according to the method described. The sheathhas three lumens in the embodiment shown. A first lumen 72 is used as aconduit for a fiber optic cable. A second lumen 74 is provided throughwhich a cutter is delivered to the work site within the intervertebraldisc. The cutter could be a laser cutter, or a mechanical cutter, suchas a rotary cutter.

A third lumen 76 is relatively larger, and provides a conduit for levageand suction. Saline or other materials may be introduced to the worksite in the disc through the lumen. Tissue that is removed, along withattendant blood and other materials, may be suctioned and evacuatedthrough lumen 76.

FIG. 30 shows the fiber optic source 78, cutter 80 and the conduit forlevage and suction 82.

The introducer penetrates the wall of the disc as described above. Theintroducer is shown as having penetrated the lateral posterior wall ofthe disc 84 in FIG. 31. The sheath is positioned within the disc throughthe introducer. The sheath is initially positioned so that its forwardend extends only slightly beyond the end of the introducer. The cutter,the fiber optic and the levage and suction are actuated, and the entireassembly, along with the introducer, are pushed to the opposite wall 86of the disc, which in this case, is the lateral anterior portion of thedisc so that the pulposa of the disc and the disc wall itself areremoved, as shown in FIG. 31. Since the materially extended sheath hasan S-shape when no pressure is applied to the sheath, there will be aslight curvature of the sheath as it marginally extends from theintroducer. Accordingly, the cut as shown in FIG. 31 is somewhat conicalin shape, rather than being straight, due to the arcuate shape of thesheath when the sheath is advanced slightly from the introducer.

The evacuation progresses outwardly. As the intervertebral disc isremoved, support must be provided for the adjoining the vertebrae. FIG.32 shows the cutter removed from the sheath, and a support member orstrut 88 placed in position using insertion or placement tool. Thesupport member or strut may be capable of inflation using, for example,saline. Accordingly, the support member or strut may be a balloon orbladder.

The sheath is progressively extended, and progressive cuts are madeusing the introducer to traverse generally linearly in and out of thedisc. As shown in FIG. 33, progressive cuts are made until the disc andassociated pulposa 90 are substantially completely removed from one sideof the introducer. The cutter may be removed from the sheath asrequired, and the placement tool inserted for placement of the supportmembers or struts within the intervertebral disc.

After one side of the disc is substantially removed, the sheath, and/orthe introducer and sheath, are rotated 180 degrees. FIG. 35. The cutteris in position in the sheath. Additional progressive passes are made bysteering and advancing the introducer and sheath, individually, or as aunit within the disc, and with the cutter in place. The sheath isprogressively extended on each pass, so that the portion of the discthat is further away from the introducer is removed with eachprogressive pass.

The S-shape of the sheath permits the material of the disc to be removedwhich is offset to each side of the introducer, even though theintroducer is advanced and retracted on what is generally a straightline dictated by the void formed in the disc through which theintroducer passes. The S-shape of the sheath allows the cutter to reachprogressively laterally as the sheath is progressively extended from theintroducer. The sheath of this embodiment, and the catheter shown inFIG. 4 through FIG. 15, and the sheath shown in FIG. 23 through FIG. 24,each have an S-shape when no material pressure is applied to thecatheter or sheath. The catheter or sheath in each embodiment of theinvention shown herein has a memory property which returns the catheteror sheath to an S-shape when no material pressure is applied to thecatheter or sheath. However, when the catheter or sheath is presentwithin the introducer, or in the case of the catheter, within the sheathfor the catheter, the S shaped element is reformed to be straight, butregains it S shape as it exits the straight lumen. The sheath ispreferred to be straight, and in some embodiments, rigid when used witha S-shaped catheter or tool having memory.

Continuing with the process of this preferred embodiment as shown in thedrawings, FIG. 37 demonstrates the final cutting away of the disc byslight protrusion of the sheath from the introducer. FIG. 38 uses thecutter with the cutter even more slightly extending from the introducerto remove the disc. However, in practice, it may be necessary to removethe entire intervertebral disc. It may be desirable to leave some of theintervertebral disc in place as a support, as long as the targeteddefective portion of the intervertebral disc is removed by the methoddescribed herein.

Various materials may be positioned within the intervertebral disc aswell as within the vertebral body using the S-shaped tool. The S-shapedtool, when used in combination with the introducer as taught herein,allows the material to be positioned about the interior wall of anintervertebral disc or a vertebral body, or within the interior of thedisc or body, as desired. Materials that are useful in treatment ordiagnosis of the spine may be positioned using the device and methodaccording to the invention. Such materials include, but are not limitedto, epoxies, cements, gels, balloons, artificial discs, and artificialnuclei. The materials may include biological materials, such asregenerative materials that induce re-growth of spine tissue.Regenerative materials that may be positioned in the disc or vertebralbody and may include morselized bone, bone substitute, or such materialsas bone morphogenic protein.

Materials may be positioned inside the disc or body by tools having alumen that provides a conduit through which fluids, including gases,liquids, gels, and semi-solids, may be transported. Materials havingelastic properties, such as balloons, may similarly be transported andinflated within the disc or vertebral body. Materials having a solidstructure may be positioned by tools that allow for grasping andreleasing the material, such as forceps, or the placement tool shown inthe drawings. FIGS. 34 and 36. The interior of the intervertebral discand the vertebral body may be accessed as disclosed herein, or by knownmethods.

In one embodiment, regenerative material is placed in the space createdby evacuation of the disc. The regenerative material 89 may bepositioned in conjunction with, or after, positioning of the spacers orstruts 88 as described above. The regenerative material will take timeto create new tissue. The spacers or struts maintain a space for thetissue. The regenerative material may be placed by the elongated tool astaught by the invention.

Material may be used to provide support for the spine where elements ofthe spine, such as when some or all the disc or the vertebral body hasbeen removed, or when these elements have suffered disease or damage.Placement of material may be performed by the elongated S-shapedplacement tool according to methods described herein. Such filler orsupport material may be regenerative material, gel, balloon material,struts, cements or other filler materials. Disc replacement devices andmaterials may be positioned by the elongated S-shaped placement tool.Spinal fusion processes may also be performed, with fixation devices andmaterials placed using the elongated S-shaped tool.

FIG. 3 shows a tool positioned at the end of the S-shaped tool 92 thatis useful for placing material, such as medicaments, spacers or struts,or regenerative material. This tool may also be used for removingobjects, tissue or material. In one embodiment, the tool has opposingspoons 94 or scoops that form a clam shell device. The user manipulatesthe opposing spoons or scoops to grasp and release material or objects.The spoons or clam shell may be manipulated from an external position bythe user through an actuator traversing the elongated portion of thetool and/or the sheath that extends to the exterior of the disc 4.

FIG. 39 shows a tool positioned at the end of the S-shaped tool that isuseful for cutting and removing objects, tissue or material. The toolhas a blade 94 at an end of the S-shaped tool 96. The blade may have asharp edge, or it may have fingers extend from it like a rake. The blademay be manipulated from an external position by the user through anactuator traversing the elongated portion of the tool and/or a sheaththat extends to the exterior of the disc 4. Tissue 42 or other materialthat is harvested by the tool may be evacuated, such as by suction. Thesuction may be provided through the tool and/or through a sheath.

Each embodiment of the tool is preferred to comprise an elongated toolhaving an S-shape, whether the tool is used as a conduit, a therapeutictool, a tissue (or object) removal tool or a placement tool. Theelongated tool comprises shape memory properties, so that the tool canbe formed for transport through the guide or lumen of the introducer.The elongated tool regains its S-shape upon exiting the guide or lumenof the introducer. Similarly to the tool shown in FIGS. 5 through 15, anintroducer and an elongated S-shaped tool can be manipulatedindependently of each other to advance and retract the introducer withinthe disc or vertebral body, and to expose as much of the S-shaped toolas is required relative to the introducer. The elongated S-shaped toolmay thereby be positioned as desired within the disc or the vertebralbody. The elongated S-shaped tool allows precise positioning of thetool, and therefore precise positioning of material. The elongatedS-shaped tool also allows gross positioning of material where precisionplacement is not required.

The procedures and processes described herein may be, and are preferredto be, performed percutaneously. The procedures and processes may beperformed using stab incision or small incision techniques, ortechniques wherein an incision of about 2.5 centimeters or less is usedto provide access for the introducer, the sheath and/or the tool.

1. A method of placing material in an interior of a mammalianintervertebral disc or vertebral body, comprising the steps of: a)forming an opening through a wall of a mammalian intervertebral disc orvertebral body; b) advancing an introducer comprising a guide throughsaid opening in said wall of the mammalian intervertebral disc orvertebral body; c) engaging said guide with an elongated placement tooland advancing said elongated placement tool along said guide, whereinsaid elongated placement tool is formed of a shape memory material andcomprises a preformed S-shape and wherein said preformed S-shape of saidelongated placement tool is deformed by said guide; d) continuing toadvance said elongated placement tool along said guide until a portionof said elongated placement tool comprising said preformed S-shape exitssaid guide into the interior of the mammalian intervertebral disc orvertebral body, whereupon the preformed S-shape of said elongatedplacement tool assumes said preformed S-shape as said elongatedplacement tool exits said guide in the interior of the mammalianintervertebral disc or vertebral body; e) positioning said elongatedplacement tool as desired within the interior of the mammalianintervertebral disc or vertebral body, wherein the elongated placementtool is selectively positioned and material is deposited at points inthe interior of the mammalian intervertebral disc or vertebral body bycombining selective advancement and retraction of the elongatedplacement tool within the interior of the mammalian intervertebral discor vertebral body with independent selective advancement and retractionof the introducer.
 2. A method of placing material in an interior of amammalian intervertebral disc or vertebral body as described in claim 1,wherein the elongated placement tool comprises a lumen through which thematerial is transported into the interior of the mammalianintervertebral disc or vertebral body.
 3. A method of placing materialin an interior of a mammalian intervertebral disc or vertebral body asdescribed in claim 1, wherein the elongated placement tool comprisesforceps that position the material within the interior of theintervertebral disc or vertebral body.
 4. A method of placing materialin an interior of a mammalian intervertebral disc or vertebral body asdescribed in claim 1, wherein the material transported into the interiorof the mammalian intervertebral disc or vertebral body is a biologicalmaterial.
 5. A method of placing material in an interior of a mammalianintervertebral disc or vertebral body as described in claim 1, whereinthe material transported into the interior of the mammalianintervertebral disc or vertebral body is a regenerative material thatinduces regeneration of spinal tissue.
 6. A device for placing materialin an interior of a mammalian intervertebral disc or vertebral body,comprising: a) an introducer for introducing an elongated placement toolinto the interior of the mammalian intervertebral disc or vertebralbody, said introducer comprising a guide; and b) an elongated placementtool formed of shape memory material and comprising a preformed S-shape,wherein said elongated placement tool engages said guide, and saidelongated placement tool is transported into the interior of themammalian intervertebral disc or vertebral body by said guide of saidintroducer, and said S-shape of said elongated placement tool isdeformable and is deformed by said introducer as said elongatedplacement tool is transported along said guide, and said elongatedplacement tool regains its preformed S-shape upon exiting said guide ofsaid introducer, wherein the elongated placement tool is constructed andarranged so that a distal end of the elongated placement tool isselectively positioned at different points of the mammalianintervertebral disc or vertebral body by combining selective advancementand retraction of the elongated placement tool within the interior ofthe mammalian intervertebral disc or vertebral body with independentselective advancement and retraction of the introducer.
 7. A device forplacing material in an interior of a mammalian intervertebral disc orvertebral body as described in claim 6, wherein the elongated placementtool comprises a lumen through which the material is transported intothe interior of the mammalian intervertebral disc or vertebral body. 8.A device for placing material in an interior of a mammalianintervertebral disc vertebral body as described in claim 6, wherein theelongated placement tool comprises forceps that position the materialwithin the interior of the intervertebral disc or vertebral body.
 9. Amethod of placing material in an interior of a mammalian intervertebraldisc or vertebral body, comprising the steps of: a) forming an openingthrough a wall of a mammalian intervertebral disc or vertebral body; b)advancing an introducer comprising a guide through said opening in saidwall of the mammalian intervertebral disc or vertebral body; c) engagingsaid guide with an elongated placement tool and advancing said elongatedplacement tool along said guide, wherein said elongated placement toolis formed of a shape memory material and comprises a preformed S-shapeand wherein said preformed S-shape of said elongated placement tool isdeformed by said guide; d) continuing to advance said elongatedplacement tool along said guide until a portion of said elongatedplacement tool comprising said preformed S-shape exits said guide intothe interior of the mammalian intervertebral disc or vertebral body,whereupon the preformed S-shape of said elongated placement tool assumessaid preformed S-shape as said elongated placement tool exits said guidein the interior of the mammalian intervertebral disc or vertebral body;e) positioning said elongated placement tool as desired within theinterior of the mammalian intervertebral disc or vertebral body byadvancing and retracting said elongated placement tool relative to saidintroducer; f) placing material in an interior of the mammalianintervertebral disc or vertebral body; and g) rotating the elongatedplacement tool relative to the introducer and performing a procedureusing said elongated placement tool on a side of the mammalianintervertebral disc or vertebral body that is opposite a first side ofthe mammalian intervertebral disc or vertebral body upon which theprocedure was performed prior to rotating said elongated placement tool.10. A method of placing material in an interior of a mammalianintervertebral disc or vertebral body as described in claim 9, whereinthe elongated placement tool comprises a lumen through which thematerial is transported into the interior of the mammalianintervertebral disc or vertebral body.
 11. A method of placing materialin an interior of a mammalian intervertebral disc or vertebral body asdescribed in claim 9, wherein the elongated placement tool comprisesforceps that position the material within the interior of theintervertebral disc or vertebral body.
 12. A method of placing materialin an interior of a mammalian intervertebral disc or vertebral body asdescribed in claim 9, wherein the material transported into the interiorof the mammalian intervertebral disc or vertebral body is a biologicalmaterial.
 13. A method of placing material in an interior of a mammalianintervertebral disc or vertebral body as described in claim 9, whereinthe material transported into the interior of the mammalianintervertebral disc or vertebral body is a regenerative material thatinduces regeneration of spinal tissue.
 14. A method of placing materialin an interior of a mammalian intervertebral disc or vertebral body asdescribed in claim 1, wherein, prior to placing material in saidmammalian intervertebral disc or vertebral body, tissue of the mammalianintervertebral disc or vertebral body is removed by an S-shapedelongated tool that comprises a cutter.
 15. A method of placing materialin an interior of a mammalian intervertebral disc or vertebral body asdescribed in claim 1, wherein, prior to placing material in saidmammalian intervertebral disc or vertebral body, tissue of the mammalianintervertebral disc or vertebral body is removed by an S-shapedelongated tool that comprises a cutter, wherein the S-shaped elongatedtool is transported to the mammalian intervertebral disc or vertebralbody by an introducer, and wherein the S-shaped elongated tool ispositioned relative to the mammalian intervertebral disc or vertebralbody by combining selective advancement and retraction of the elongatedplacement tool with independent selective advancement and retraction ofthe introducer.
 16. A method of placing material in an interior of amammalian intervertebral disc or vertebral body as described in claim 1,wherein the material deposited by the elongated placement tool is aspacer.
 17. A method of placing material in an interior of a mammalianintervertebral disc or vertebral body as described in claim 1, whereinthe material deposited by the elongated placement tool comprises a firstmaterial and a second material, wherein the first material is a spacer,and the second material is a regenerative material that inducesregeneration of spinal tissue.
 18. A method of placing material in aninterior of a mammalian intervertebral disc or vertebral body asdescribed in claim 1, wherein the material deposited by the elongatedplacement tool comprises a first material and a second material, whereinthe first material is a spacer, and the second material is aregenerative material that induces regeneration of spinal tissue,wherein the spacer is constructed and arranged to maintain a spacebetween a first vertebral body and a second vertebral body, and whereinthe regenerative material is positioned within said space.
 19. A devicefor placing material in an interior of a mammalian intervertebral discor vertebral body as described in claim 1, wherein the elongatedplacement tool comprises a lumen through which the material istransported, and the lumen opens near a distal end of said elongatedplacement tool, wherein the material is transported into the interior ofthe mammalian intervertebral disc or vertebral body through the lumen,and the material is positioned in the mammalian intervertebral disc orvertebral body by selectively positioning the opening by combiningselective advancement and retraction of the elongated placement toolwithin the interior of the mammalian intervertebral disc or vertebralbody with independent selective advancement and retraction of theintroducer.
 20. A method of placing material in an interior of amammalian intervertebral disc or vertebral body as described in claim 9,wherein, prior to placing material in said mammalian intervertebral discor vertebral body, tissue of the mammalian intervertebral disc orvertebral body is removed by an S-shaped elongated tool that comprises acutter.
 21. A method of placing material in an interior of a mammalianintervertebral disc or vertebral body as described in claim 9, wherein,prior to placing material in said mammalian intervertebral disc orvertebral body, tissue of the mammalian intervertebral disc or vertebralbody is removed by an S-shaped elongated tool that comprises a cutter,wherein the S-shaped elongated tool is transported to the mammalianintervertebral disc or vertebral body by an introducer, and wherein theS-shaped elongated tool is positioned relative to the mammalianintervertebral disc or vertebral body by combining selective advancementand retraction of the elongated placement tool with independentselective advancement and retraction of the introducer.
 22. A method ofplacing material in an interior of a mammalian intervertebral disc orvertebral body as described in claim 9, wherein the material depositedby the elongated placement tool is a spacer.
 23. A method of placingmaterial in an interior of a mammalian intervertebral disc or vertebralbody as described in claim 9, wherein the material deposited by theelongated placement tool comprises a first material and a secondmaterial, wherein the first material is a spacer, and the secondmaterial is a regenerative material that induces regeneration of spinaltissue.
 24. A method of placing material in an interior of a mammalianintervertebral disc or vertebral body as described in claim 9, whereinthe material deposited by the elongated placement tool comprises a firstmaterial and a second material, wherein the first material is a spacer,and the second material is a regenerative material that inducesregeneration of spinal tissue, wherein the spacer is constructed andarranged to maintain a space between a first vertebral body and a secondvertebral body, and wherein the regenerative material is positionedwithin said space.
 25. A device for placing material in an interior of amammalian intervertebral disc or vertebral body as described in claim 9,wherein the elongated placement tool comprises a lumen through which thematerial is transported, and the lumen opens near a distal end of saidelongated placement tool, wherein the material is transported into theinterior of the mammalian intervertebral disc or vertebral body throughthe lumen, and the material is positioned in the mammalianintervertebral disc or vertebral body by selectively positioning theopening by combining selective advancement and retraction of theelongated placement tool within the interior of the mammalianintervertebral disc or vertebral body with independent selectiveadvancement and retraction of the introducer.